var inputChande = document.getElementsByClassName('changeinput');
var inputBox = document.querySelectorAll('form>div:not(.post)');
var index = 0;
var lastIndex = 0;
var submitValue = document.getElementsByClassName('submit')[0];


for (var i = 0; i < inputBox.length; i++) {
  inputBox[i].index = i;
  inputBox[i].onmouseover = function () {
    index = this.index;
    inputChande[index].classList.add('add_widthC');
  }
}